Progress and Status of gated IPM collaboration: FY2018 KEK/J-PARC - PowerPoint PPT Presentation

US-Japan Meeting on Accelerators and Beam Equipment for High-Intensity Neutrino Beams: 19, 21/03/2019 Progress and Status of gated IPM collaboration: FY2018 KEK/J-PARC Kenichirou Satou / Introduction ・ Issue on gain degradation of MCP detector ・ Merit of the gated IPM / Project plan and progress ・ New plan: extended by 2 years ・ HV gating system Discharge problem -> Delayed schedule ・ How to improve a withstand voltage How to connect cables? ・ Performance check ・ 3rd IPM workshop at J-PARC / Summary

Issue on a charged particle detector, Micro Channel Plate (MCP) Local gain degradation after the long-term operation of 9 years Photo of IPM Profile measurement principle ・ MCP is used as a charged particle detection and signal amplification devise and its gain uniformity is essential for the profile measurement MCP gain -25% ・ The local gain decrease with increase the integrated output charge, and thus it is severe at the center area ・ MCP devise is expensive and cannot be replaced easily Beam profiles controlled by the local bump orbits Beam center Effective area Effective area of MCP Photo of the detector, MCP

Solution: HV DC -> Pulse mode operation Local gain decrease can be expressed as Integrated time of measurement Beam center fluctuation Integrated output charge Beam on ratio ∙ ෩ ∆𝐇 𝒚 ∝ 𝑅 𝑦 ∝ 𝐻 0 𝑊 𝑐𝑗𝑏𝑡 ∙ ෤ 𝜍 𝑦 − 𝑔 𝑦0 𝑦 𝐽 0 ∙ 𝑈 ∙ 𝐸 𝑐𝑓𝑏𝑛 ∙ 𝑬 𝑱𝑸𝑵 Local gain change Duty of IPM operation MCP gain set Averaged intensity Averaged profile measured Gated IPM system can Gated system optimize this parameter On mode Off mode Courtesy of Randy Thurman-Keup, profile measured by the IPM @ FNAL with pulsed HV: From the presentation file of US/Japan monitor meeting at FNAL, 2015. When 100Hz 1% duty switching operation is used ( 𝑬 𝑱𝑸𝑵 : 𝟐 → 𝟏. 𝟏𝟐 ) , only 20 turn profiles will be selected for each pulse. MCP life will be extended to 100 times 𝑭 × 𝑪 (𝒘 𝒜 = 𝑭 𝒚 𝑪 𝒛 ) drift sweeps the charged longer than that in the case of non-gated system. particle away from the area of MCP detector

Project plan and progress Some items are delayed And the schedule is extended New item is added • FY2019 • FY2016 – Install – Design of the HV switching module • HV gating system: New PS and – Performance check with test circuit control unit – Particle tracking simulation of gated IPM – Performance check of the gated IPM system system • FY2017 • Beam study • – Simulation using a code IPMsim3D Construction – Feasibility study of an e-scanner for • HV switching module -> Delayed due to J-PARC MR corona and flush over discharge problem • • New faraday cage Future plan – • Performance check of the HV switching To check profile data consistency between gated IPM and e-scanner module Almost finished • Simulation using the code IPMsim3D – Particle tracking simulation of gated IPM • FY2020 system • – Performance check of the gated IPM FY2018 system – Install – Some modifications will be made for • New faraday cage -> for both H, V IPMs the gated IPM system if needed • HV switching module -> Delayed: PS and – Feasibility study of an e-scanner for control unit will be delivered soon (3/19) J-PARC MR – Performance check of the new gated IPM system -> Delayed

HV gating system LED: HV on, Gate on, Polarity(Pos, Neg), Power on(for each PS), Fault(HTS301-03-GSM) Lemo TTL FG:Gate generator 1 2 +5V 0.4A 3 1A fuse 4 Lemo Capacitor 5 Polarity setting TTL Hi:Posi, Lo:Neg G61C841P 1μF +30kV DC PS 2A fuse HFR30-30P HVout 6 Vin:+24V 1.7A typ. P 0～ 10V PLCout +24V 1.7A typ 7 GND=CASE Voltage matching by Resistors P 1MΩ Oil Capacitor HTS301-03-GSM 8 1kΩ GND=CASE P 1μ F 9 Vcont:0-5V P Cnt. Inp 3-10V 10 Vref 5V Door switch PLC P GND 11 Remote HV on/off GND Normal Close P Hi:On, Low:Off 5VDC 0.4ADC Relay switch 12 Imon:5V/定 格 Zout=1kΩ P To PLC Imon Fault TTL HV out 13 Lemo 4pin Vmon:5V/定 格 Zout=1kΩ P GND Switched 30kV +HV Polarity change out Vmon To PLC Lemo?? -HV -30kV DC PS G61C841P MOS switch HFR30-30N HVout 6 Vin:+24V 1.7A typ. N 7 GND=CASE N 1MΩ 8 GND=CASE 1kΩ N 9 Vcont:0-5V N 10 Vref 5V N 12 Remote HV on/off GND N 12 Imon:5V/定 格 Zout=1kΩ N 13 Vmon:5V/定 格 Zout=1kΩ N Pulsed HV Relay switch ± 20kV DC PS Discharging HMBR-20R0.6 G61C841P HV out 14 NC DC 15kV Display V set mon 15 Vcont:0-10V HVout Lemo?? 16 NC NC 1MΩ 17 Display Vmon 18 Vmon:10V/定 格 19 Polarity setting TTL Hi:Posi, Lo:Neg +24V 1.3A typ 20 COM 21 Vin return Vin:+24V 1.3A typ. 22 DC HV Vin return 23 Door switch NC PLC 24 (Short=ON, Open=FF) High voltage power supply Hi:On, Low:Off Normal Close 2A fuse Remote HV on/off GND 25 Oil Capacitor Display Imon Imon:10V/定 格 26 1μ F NC 27 Capacitor 28 Vin:+24V 1.3A typ. Compact:19 inch rack mount size Door switch Hi,Open:HVout Low,Short:GND 1μF 29 Hi:On, Low:Off PLC Normal Close Operational max. HV: 25kV Withstand HV: ≥ 30kV Pulsed HV PS Controller

Local/Remote switch Remote/Local Switch GND pin Local/remote On/Off: Gate HV gate on/off PLC TTL on/off Note:50Ω matching Analog out LEMO Gate out LED Output control: Gate 1 FG BNC Trigger 2 Timing Trigger Timing module Analog out LED +5V 0.4A 1A Fuse 3 Analog out 4 LED Polarity set Polarity set PLC TTL on/off 5,19 4A Fuse Analog out 6 P ,6 N ,22,28 LED HV PS controller GND=CASE +24V 3A typ Local/remote 7 P ,7 N ,21,23 Dial set Vcont GND=CASE GND=CASE 8 P V set HV value set 9 P PLC 0-10V out 0-5V 10 1kΩ ? Analog out GND=CASE P Display Local/remote On/Off: HV output Dial set HV on/off HV on/off Door switch 11 P PLC TTL on/off Analog out 1kΩ ? LED Analog out 2 12 P Display 1kΩ ? filter 13 Analog out 2 P Display 1kΩ ? Gate signal from a function generator Control by the PLC 9 N : Monitor signals (Current, Voltage) 10 N 11 N 12 N 13 N GND=CASE Dial set 14 Vcont 15 Analog out 16 Display 17 Analog out 18 19 Display GND=CASE 20 21 22 23 24 HV on/off 25 Analog out LED Analog out 26 Display 27 28 HV on/off 29

How to connect HV cables Improved withstand voltage: 20kV ⇒ >30kV 4) Put silicone oil compound and inserted into a heat shrinkage tube 1) Connect a resistor and cables with sleeve Resister Sleeve Heat shrinkage tube 2) Round the corner with a sandpaper Silicone oil compound 3) Paint the surface with polyvinyl-based resin 5) Cover again the junction with the tube as well as the cut-edge of the cable shield Polyvinyl-based resin

Performance check: Dummy load A SPICE model can reproduce the performances HV cable capacitor 30kV DC PS CMOS switch Capacitor 20kV DC PS Dummy load SPICE model for this test setup 10Hz Charging time

SPICE model of Gated IPM Rise/Fall time: 15.7μs Pulse width : 200 μs Gated IPM chamber 200μs Cycle : 10 Hz Duty : 0.2% Max. HV : 0.9 × 30kV

Simulation work Gated IPM design, Feasibility study on e-scanner Electron and ion motion simulation are now on going using a home-made 3D particle tracking simulator, IPMsim3D . Beam intensity of bunch train Gaussian profile Successive Over Relaxation ( SOR ) to estimate Poisson eq. ・ Assumed to be 2D : Relativistic ・ Rectangular grid Grid data from POISSON /Superfish (2D) CST STUDIO SUITE (3D) ・ Rectangular or Cubic grid 3D particle tracking 4th order Runge- Kutta method Ionization cross section Single differential cross section for H, He, H 2 , CH 4 , NH 3 , and H 2 O Double differential cross section for H, and He Flow chart of IPMsim3D

IPM workshop at J-PARC: 18-20/9/2019 International workshop on non-invasive beam profile monitors for hadron machines and its related techniques: 3rd IPM workshop https://conference-indico.kek.jp/indico/event/55/ In total, 14 talks and 1 special seminar 2 talks on Gated IPM “IPM system for J - PARC MR: Magnet issues and Gated System”, K. Satou “Present Status of Non - Invasive Profile Monitors at FNAL”, Dr. Randy J-PARC seminar “MCPs and MCP based detectors”, Dr. Raquel Ortega Comino ( Photonis)